1. Field of the Invention
Embodiments relate to methods for detecting the status of a telephone receiver and communications terminals with a telephone receiver.
2. Background of the Art
Communications terminals (telephones or similar devices) for voice communications are generally equipped with telephone receivers (frequently also called “handsets”), which feature a loud speaker (earpiece) and a microphone (mouthpiece) and are connected to a base device (the actual communications terminal) or a base station by means of an access line or a wireless connection. Furthermore, other components of the communications terminal can also be integrated into a telephone receiver, for example, a keypad, a display device, etc., so that here, in the broader sense, common cordless telephones or cell phones also constitute telephone receivers. So-called “headsets” in non-wireless or wireless (“BLUETOOTH® certified headsets”) models are also telephone receivers.
Besides functioning as a microphone and loudspeaker, a telephone receiver, at least in the case of commonly used non-wireless communications terminals (desk telephones), also controls the receiving (incoming calls) and the ending of a communication connection in that this receiver is removed from or placed on the base device of the communications terminal. For this purpose, the communications terminal (base device) is generally equipped with a so-called hook switch, a photoelectric sensor, or a magnetic switch (“reed contact”), in order to detect the status (on-hook, off-hook) of the telephone receiver.
There are also known devices in which a pressure switch is integrated into the surface of the telephone receiver, which detects whether or not the telephone receiver is resting on a table top or something similar. In the case of cordless and cell phones, the function of a hook switch is generally emulated by one or several pushbuttons, wherein a user makes an appropriate entry for receiving a call or ending a communication connection. For this, it must be noted that, in the case of the devices mentioned first (hook switch, photoelectric sensor), the corresponding technical device (hook, photoelectric sensor) can also be operated manually, that is, using a finger or a hand, for example, without the telephone receiver actually having to be on-hook.
With the known devices for detecting the status of telephone receivers (and thus also of cellular communications terminals), it has proven to be disadvantageous that complex mechanical and/or electrical systems must be used for detecting the status. This applies to both the mechanically constructed hook switch and the “electronic” solutions with pushbuttons, photoelectric sensors, magnetic contacts, or similar devices. A further disadvantage is that the aforementioned devices (hook switch, photoelectric sensor, etc.) can frequently also be operated manually, which means, for example, that the status “on-hook” can also be erroneously determined when the telephone receiver or the cellular terminal is still located at the user's ear.